用@Embeddable保存实体时的PropertyAccessException

map a many-to-many association with extra columns tutorial 但不是很成功。

所以我有以下实体。。。

@Data
@Entity
@Table(name = "PEOPLE")
public class People implements Serializable {

    @Id
    @SequenceGenerator(name = "people", sequenceName = "people_id_seq", allocationSize = 1)
    @GeneratedValue(strategy = GenerationType.AUTO, generator = "people")
    private long peopleId;

    private String peopleName;

    @ToString.Exclude
    @EqualsAndHashCode.Exclude
    @OneToMany(
            mappedBy = "people", 
            cascade = CascadeType.ALL, 
            orphanRemoval = true
    )
    private List<PeopleStats> peopleStats;

    public void addStats(Stats stats) {

        if (this.peopleStats == null) {
            this.peopleStats = new ArrayList<>();
        }

        PoepleStats pStats = PoepleStats.builder().people(this).stats(stats).build();

        this.peopleStats.add(pStats);
    }
}

@Data
@Entity
@Table(name = "STATS")
public class Stats implements Serializable {

    @Id
    @SequenceGenerator(name = "stats", sequenceName = "stats_id_seq", allocationSize = 1)
    @GeneratedValue(strategy = GenerationType.AUTO, generator = "stats")
    private long statsId;

    private String statsName;
    private String statsDescription;

}

@Data
@Entity
@Table(name = "PEOPLE_STATS")
public class PeopleStats implements Serializable {

    @EmbeddedId
    private PeopleStatsId peopleStatsId;

    @ManyToOne(fetch = FetchType.LAZY)
    @MapsId("peopleId")
    private People people;

    @ManyToOne(fetch = FetchType.LAZY)
    @MapsId("statsId")
    private Stats stats;

    private long value;

}

@Data
@Embeddable
@EqualsAndHashCode
public class PeopleStatsId implements Serializable {

    // Putting @Column(name = "people_id") or not doesn't seem to have any effect
    private long peopleId;
    // Same goes for this
    private long statsId;

}

然后进行以下单元测试。。

@RunWith(SpringRunner.class)
@DataJpaTest
public class PeopleRepositoryTest {

    @Autowired
    private TestEntityManager entityManager;


    @Test
    public void testSavePeople() {

        // People object created
        people.addStats(Stats.builder().statsId(new Long(1)).statsName("a").statsDescription("b").build());

        this.entityManager.persistAndFlush(people);
    }
}

Hibernate: create table people_stats (value bigint not null, people_people_id bigint not null, stats_stats_id bigint not null, primary key (people_people_id, stats_stats_id))

这是stacktrace。。

javax.persistence.PersistenceException异常: org.hibernate.PropertyAccessException网站:无法设置字段值 1 com.sample.shared网站.实体.PeopleStatsId.peopleId]设置者 com.sample.shared网站.实体.PeopleStatsId.peopleId在 org.hibernate.internal公司.前ceptionConverterImpl.convert转换(前java:149) org.hibernate.internal公司.前ceptionConverterImpl.convert转换(前java:157) 在 org.hibernate.internal公司.前ceptionConverterImpl.convert转换

我碰到这个 similar issue ,有解决方案但不起作用。在尝试了第一个解决方案之后,即创建 new PeopleStatsId @EmbeddedId ,我也犯了同样的错误。

有人能带我走吗?谢谢。

github .

更新2

public void addStats(Stats stats) {

        if (this.peopleStats == null) {
            this.peopleStats = new ArrayList<>();
        }

        PeopleStats pStats = PeopleStats.builder().peopleStatsId(new PeopleStatsId()).people(this).stats(stats).build();

        this.peopleStats.add(pStats);
    }

它现在正在抛出分离实体错误。

原因:org.hibernate.persistentobject异常:分离的实体 org.hibernate.event网站.内部.DefaultPersistEventListener.onPersist(默认java:124的persistentEventListener.java) ... 68个以上

更新3 :

我变了 CascadeType.ALL 到 MERGE 它似乎解决了这个问题,但我不知道为什么。我甚至删除了更新2中关于 .peopleStatsId(new PeopleStatsId()) 它也能工作。现在我更困惑了。

在人民课上:

    @OneToMany(
            mappedBy = "people", 
            cascade = CascadeType.MERGE, 
            orphanRemoval = true
    )
    private List<PeopleStats> peopleStats;

    public void addStats(Stats stats) {

        if (this.peopleStats == null) {
            this.peopleStats = new ArrayList<>();
        }

        PeopleStats pStats = PeopleStats.builder().people(this).stats(stats).build();

        this.peopleStats.add(pStats);
    }